Birds

Birds are warm-blooded vertebrate animals that have wings, feathers, a beak, no teeth a skeleton in which many bones are fused together or are absent, and an extremely efficient,, one-way breathing system. Flying birds have strong, hollow bones and powerful flight muscles.
Most birds can fly. Birds have a very strong heart and an efficient way of breathing - these are necessary for birds to fly.Birds also use a lot of energy while flying and need to eat a lot of food to power their flight.
Not all flying animals are birds; and not all birds can fly. The ability to fly has developed independently many times throughout the history of the Earth. Bats (flying mammals), pterosaurs (flying reptiles from the time of the dinosaurs), and flying insects are not birds.
MOVING: Flying, Running,and Swimming

The fastest running bird is the ostrich, but it cannot fly. The ostrich is also the fastest two-legged runner of all the animals on Earth. The ostrich is the largest bird. |
Bird locomotion is quite varied; most can fly, some can run very well, some swim, and some do combinations of these. Some birds cannot fly.

Most birds can fly. Flying birds' wings are shaped to providelift, allowing them to fly. These light-weight animals have adapted to their environment by flying, which makes them efficient hunters, lets them escape from hungry predators (like cats), and takes them away from harsh weather (migration).

The peregrine falcon is one of the fastest birds, and has been clocked at 90 miles per hour in a dive (and some people say that they can dive at over 200mph).

Feathers:

Male birds are frequently more brightly colored than females. This is to attract females for mating purposes. The females are more dully colored, helping to camouflage her when she is caring for her young (although the male often cares for the young, with or without the female). The peacock (the male peafowl is pictured above) is very brightly colored. The peahen (the femalepeafowl) is dull brown in color. |
There are different types of feathers and they each have different uses.

Feathers are used for:
* Flying - flight feathers, grow in the wings and the tail.
* Thermal insulation - soft down feathers that grow close to the skin keep birds from getting too cold or too hot
* Courtship and mating displays - these vary tremendously from species tospecies.

Diet:

Some amazing hunters, like eagles, have eyesight that is five to six times sharper than a person's. They can spot small prey from a mile away. |
Modern-day birds do not have any teeth (ancient birds did have teeth). Birds have a tongue, but unlike our tongue, a bird's tongue has a bone in it.
Birds spend most of their time looking for food. Most birds are insectivores (theyeat insects). Some birds, like owls and eagles, are carnivores (meat-eaters). Some birds, like the hummingbird, grouse, and Canada goose, are mostly herbivores (plant-eaters). Other birds, like starlings, are omnivores (plant- and meat-eaters). Some birds (like the toucan) are fructivore (fruit-eaters)
Birds mostly use their keen eyesight to find food. They use their beak and their claws to getbugs, worms, small mammals , fish, fruit , grain, or nectar.

Birds play a very important part in the natural control of insects and in the dispersal of seeds. Some birds, like the tiny, nectar-eating hummingbird are important pollinators of some flowering plants.

Nests and Eggs:

The ostrich lays the largest birds' eggs; their eggs are up to 4.5 x 7 inches (11 x 18 cm) across and weigh3 pounds (1400 g). |
Birds bear their young in hard-shelled eggs which hatch after some time. Some birds, like chickens, lay eggs each day, others (like the maleo) may go for years between laying eggs.
Birds build nests for breeding in trees, on cliffs, or on the ground. Most birds are taken care of by at least one parent until they are able to fly and get their own food.

Bird |...